The Use of In Vitro Systems for Evaluating Immunotoxicity: The Report and Recommendations of an ECVAM Workshop.

This is the report of a workshop organised by the European Centre for the Validation of Alternative Methods (ECVAM). ECVAM's main goal, as defined in 1993 by its Scientific Advisory Committee, is to promote the scientific and regulatory acceptance of alternative methods that are of importance to the biosciences and which replace, reduce or refine the use of laboratory animals. One of the first priorities set by ECVAM was the implementation of procedures that would enable it to become well informed about the state-of-the-art of non-animal test development and validation, and the potential for the possible incorporation of alternative tests into regulatory procedures.

Microarray-based in vitro test system for the discrimination of contact allergens and irritants: identification of potential marker genes.

Background: Animal tests have been used to characterize the potential of chemicals to produce allergic contact dermatitis, but this approach is increasingly a matter of public and political concern. Our aim was to develop and validate an alternative in vitro test that can identify contact allergens.

Methods: We developed a targeted microarray containing oligonucleotide probes for 66 immune-relevant genes and analyzed gene expression in monocyte-derived dendritic cells (Mo-DCs) treated with 1 irritant (SDS) and 2 prominent contact allergens, nickel and Bandrowski's base (BB), which is the oxidation product of the most important hair dye allergen, p-phenylenediamine.

In vitro effects of GSM modulated radiofrequency fields on human immune cells.

Despite the important role of the immune system in defending the body against infections and cancer, only few investigations on possible effects of radiofrequency (RF) radiation on function of human immune cells have been undertaken. Aim of the present investigation was therefore to assess whether GSM modulated RF fields have adverse effects on the functional competence of human immune cells. Within the frame of the multidisciplinary project "Biological effects of high frequency electromagnetic fields (EMF)" sponsored by the National Occupation Hazard Insurance Association (AUVA) in vitro investigations were carried out on human blood cells.

The use of flow cytometric methods in acute and long-term in vitro testing.

One principal demand for in vitro screening for toxic effects is the ease of performance and the high throughput of test methods. Flow cytometry offers the possibility to study several parameters simultaneously, e.g.

Flow cytometric methods used as screening tests for basal toxicity of chemicals.

Aim of the present study was to evaluate the suitability of flow cytometry to test in vitro effects of toxicants. Flow cytometry offers the possibility to study several parameters simultaneously, e.g.

In vitro studies on the toxicity of isoniazid in different cell lines.

The aim of the present study was to investigate in vitro the mechanism of toxicity of isoniazid (= INH), the drug most widely used for treatment of tuberculosis. The human hepatoma line HepG2, the human lymphoblastoid line AHH-1 and the murine lymphoma cells YAC-1 were used as test systems. Active cell death (= apoptosis) and necrosis were detected by different flow cytometric methods: the binding of annexin V to the cell membrane and staining with propidium iodide (PI), the TUNEL assay for detection of DNA fragmentation and the occurrence of a sub G1 peak in cell cycle histograms.

Application of the popliteal lymph node assay in immunotoxicity testing: complementation of the direct popliteal lymph node assay with flow cytometric analyses.

The popliteal lymph node assay (PLNA) has been proposed to measure the immunosensitizing potential of chemicals. The direct PLNA detects an immunomodulating effect but does not give insight into the mode of action of the chemical under test. Modifications of this test have been proposed, but they are difficult to perform in routine toxicity testing and require many animals.